Mold assembly for forming pregrouted ceramic tile sheets



Judy 6, 3955 l A AERNE''HY MOLD ASSEMBLY FOR FORMING PREGROUTE'D OERIGTILE SHEETS Filed Nov. 28. 1960 July 6, i965 1. AABERNETHY ETAL3,392,557

MOLD ASSEMBLY FOR FORMING PREGROUTED CERAMIC TILE SHEETS Filed Nov. 28.1960 8 Sheets-Sheet 2 ymvxswroks m A. Aam/mw ROBERT l! WIL ATTORNEYSJuly 6, 1965 3,192,567

. MOLD ASSEMBLY Fon Pomme PREGROUTED CERAMIC TILE SHEETS l. A. ABERNETHYE11-AL a sheets-sheet s Filed Nov. 28, 1960 July 6, 1965 MOLD ASSEMBLYFOR FORMING PREGROUTED CERAMIC TILE SHEETS Filed NOV. 28, 1960 8Sheets-Sheet 4 INVENTORS IPA ABIR/YETHY ROBERT MIM/L HAROL RFE/CHIEFSTEPHEN J CABLE ATTORNEYS Jly 6, i955 3,192,567

HOLD ASSEMBLY FOR FRMING PREGROUTED CERAMIC TILE SHEETS Filed Nov. 28,w60

n. A. AEEYRNETHY ETAL ATTORNEYS' July 6, 1965 l. A. ABERNETHY ETAL3,192,567

MOLD ASSEMBLY FOR FORMING PREGRDUTED CERAMIC TILE SHEETS Filed Nov. 28,1960 8 Sheets-Sheet 6 Egg. 12

5N I'OR IRA 4.4 NE T HY S BER T IY. V411 HRULH I?. FEICH'EI? STEPHEN J6481.5

ATTORNEYS July 6, 1965 l. A. ABERNETHY ETAL 3,192,567

HOLD ASSEMBLY FOR FORHING PREGROUTED CERAMIC TILE SHEETS Filed Nov. 28.196D 8 Sheets-Sheet 7 INVENI' ORS El' M s# ..9 v de@ dnn-c,

Wk ATTORNEYS ai mi l. A. ABERNETHY ET Ii II Wil/l l MOLD ASSEMBLY FORFORMING PREGHOUTED CERAMIC -TILE SHEETS July 6, 1965 Filed Nov. 2a. lesom m o m M9010 RJ'TCHTFR STEPHEN l CABLE MOLD ASSEMBLY FOR FOG PREGRUTEDCERAMIC TILE SHEETS Ira A. Abernethy, Canton, Robert W. `Vail, Burton,Harold E. Eeichter, Massillon, and Stephen Il. Cable, Canton, Ghio,assignors to United States Ceramic 'Eile Co.,

Canton, Uhio, a corporation oi Delaware Filed Nov. 28, 1960, Ser. Non`72,ll3 3 Claims. (Cl. i8-36) This invention relates to pregrouted tileand more particularly to an apparatus for forming pregrouted sheets ofceramic wall tile.

In commonly assigned copending applications Serial Nos. 33,657 filedJune 3, 1960, now abandoned, and 40,- 864 tiled July 5, 1960, there isdisclosed a novel sheet arrangement for pregrouted ceramic tile. Thepregrouted sheets of those applications, both as floor and wall tiles,provide arrangements which avoid the necessity for the tiles to be setindividually by hand on the surface to be covered. At the present time,hand grouting' is used quite extensively in that it is necessary toapply grouting cement or similar grouting material between theindividual tiles after they have been placed on the wall. The ultimateappearance of the tiled surface depends importantly upon the neatnessand accuracy with which the tile mechanic performs this groutingoperation. Tile grouting as practiced is a laborious hand operationrequiring a high degree of skill and a good deal of time and painstakinglabor greatly increasing the cost of tile in stallation.

The present invention provides a novel apparatus for producing the tilesheets disclosed in the aforementioned copending applications, and whileuseful in conjunction with the installation of any type of ceramic tile,is particularly suited for use with the larger wall tile. The presentinvention provides a molding apparatus for filling up the spaces betweena plurality of individual ceramic tiles to accomplish a commercialsurface grout finish on the completed tile sheet, at least equal inappearance to the best hand-tiled surface. An important feature of thepresent invention lies in the fact that the finished sheets may betrimmed at the factory if desirable to compensate for any warping orsize variation of the individual tiles so as to provide an accuratelydimensioned tile surface with uniform grout lines.

lt is therefore a primary object of the present invention to provide animproved apparatus for forming pregrouted ceramic tile sheets.

It is another object of the present invention to provide a commercialmold for pregrouting tiles so that the tiles may be set at the point ofinstallation without any hand grouting.

Another object of the present invention is to provide a mold assemblyfor producing tile sheets and assemblies with a uniform grout line.

Another object of the present invention is to provide an arrangement forproducing pregrouted tile assemblies with exible resilient groutingjoints between individual tiles so that stress cracking of the tiles andcrazng and cracking of the grouting material is eliminated or minimized.

Another object of the invention is to provide an arrangement forproducing pregrouted ceramic tiles with plastic grouting material whichmay be varied in color and texture to provide a variety of visualetfects.

Another object of the present invention is to provide improved moldapparatus for producing pregrouted ceramic tile.

3,192,567 Patented July 6, 1965 E .w i t These and further objects andadvantages of the invention will be more apparent upon reference to thefollowing specification, claims and appended drawings wherein:

FIGURE 1 shows a twelve-tile pregrouted ceramic tile sheet constructedin accordance with the present invention;

FIGURE 2 is a perspective view of one of the two mold sections used inconjunction with the present invention;

FIGURE 3 is a longitudinal cross-section taken along line 3-3 of FIGURE2 through the bottom mold section;

FIGURE 4 is a longitudinal cross-section similar to FIGURE 3 through thetop mold section;

FIGURE 5 is a partial transverse section through the bottom mold sectiontaken along line 5--5 of FIGURE 2;

FIGURE 5a is an enlarged view of one of the intermediate grooves in thebottom rnold section of FIG- URE 5;

FIGURE 6 is a partial transverse cross-section similar to FIGURE 5vthrough the upper mold section;

FIGURE 7 is a cross-section through a corner of the mold taken alonglines 7--7 of FIGURE 2;

FIGURE 8 is a plan View of one of the silicone rubber gaskets used inconjunction with the present invention;

FIGURE 9 is a cross-section through the gasket taker along line 9 9 ofFIGURE 8;

FIGURE l0 is a cross-section through the gasket taker along line lll-llof .FIGURE 8;

FIGURE ll shows the lower mold section with the dividing frame about tobe placed thereon;

FIGURE 12 illustrates the manner of placing the ceramic tiles in thelower mold section;

FIGURE 13 shows the two mold sections clampec together and turned overfor the application of liquic` grouting material;

FIGURE 14 is a partial cross-section through an in terior portion of themold assembly;

FIGURE 15 is a partial cross-section through a groutec` edge of the moldassembly;

FIGURE 16 is a partial cross-section through a non grouted edge of themold assembly;

FIGURE 17 shows a modified open mold assembly and FIGURE i8 is a partialcross-section through a groutec edge of the mold assembly of FIGURE 17.

Referring to the drawings, FIGURE 1 shows a pre grouted tile sheetgenerally indicated at 1li composed o twelve individual ceramic tiles14. While the presen invention is applicable to all types and sizes ofceramh tile, the tiles 14 are preferably 4% X 4% 'Ji ll/g inche*` thickcushion edge ceramic wall tile. The upper surface: of the tiles areglazed and the edges are precision ground The tile sheet illustrated inFIGURE 1 is four tiles wid: and three tiles long; however, any'reasonable numbei of tiles may be joined to form a unitary tile sheet.

Between each tile is a uniform line of grout of suitabli thermosettingresin 12. A full width line of grout mate rial is also supplied to twoadjacent edges 16 and It of the tile sheet while edges 20 and 22 aregrout free While the present invention is described in conjunctior witha tile sheet having grouting material on two adja cent edges it isunderstood that the invention is equall applicable to the formation ofsheets with grout on ani of the edges desired. The grout material ispreferablj a tiexible, elastomeric thermosetting plastic but other typeof grout material may also be used for the pregroutin; of the tile.Preferred grout materials include polyure thane and polyvinyl chloride.When utilizing a viny the tiles 14 by applying a primer to the tile edgeprior to placing the assembly in the mold, as more fully describedbelow.

`FIGURE 2 illust-rates a simplified perspective view of the lower moldsection 24 used in making the tile sheet of FIGURE 1. Portions of themold 24 are shown as broken away t-o illustrate the nature of the moldconstruction. FIGURES 3 and 4 are longitudinal cross-sections throughthe lower mold section 24 and a corresponding upper mold section 26respectively. FIGURE 3 is taken along line 3-3 of FIGURE 2. FIGURES 5and 6 are partial crossscctions through the lower and upper moldsections 24 and 26 respectively, with the lower half section in FIGURE 5taken along line 5 of' FIGURE 2.

The lower and upper molds 24 and 26 are similar in construction exceptfor the shape of the grooves formed therein. Lower section 24 isprovided with a series of longitudinal grooves 28 and a second series oftransverse grooves 30. An enlarged view of one of the intermediategrooves 28 is illustrated in FIGURE 5a. Upper mold 26 similarly isprovided with longitudinal grooves 32 and transverse grooves 34. Grooves32 and 34 of the upper mold are all of rectangular cross-section. Theintermediate grooves on the lower mold section, as best seen at 28 inFIGURE 5a, taper downwardly to a central at portion 36. Edge grooves 38,40, 42 and 44 in the lower mold are all formed with a right angleportion around the outer edge of the mold and have a taper similartogroove 28 at the groove edge facing the center of the mold.

Both mold sections are preferably formed of aluminum or other good heatconducting, quick cooling metal. They form an open waie-like gridpattern wherein the crisscrossing grooves are separated by open-endedrectangular wells 45. This open waflie-like grid pattern permits greateraccess of air or other heating medium to the surfaces of the tile and tothe grout material during the `molding operation. As best seen inFIGURES 3-6, the transverse edges of the molds are provided with matingbosses 48 and 50, having clamping pins 52 and 54 received therein topermit the mold sections to be clamped together. Pins 52 and 54 may besecured in suitable cavities in the bosses which latter are threaded at56 and 58 for the reception of set screws, Somewhat similar bosses areillustrated by dashed lines at 60, 62, 64 and 66 along the longitudinaledges of both mold sections in FIGURES 3 and 4. These bosses similarlyreceive clamping pins secured by set screws in the manner of the bosses48 and 50 described above. Clamping bosses 68, 70, 72 and 7d are alsoprovided around the opposite edges of the molds in FIGURES 3-6.

Besides the dilierent cross-sectional configurations of the grooves inthe upper and lower mold sections, the single remaining differencebetween the two mold sections is best illustrated .in FIGURE 7 takenalong line 7-7 of FIGURE 2. This ligure shows the filling sprue 76provided in the lower mold section to permit access of fluid groutmaterial to the spaces intermediate the tiles. As shown, filling sprue76 is threaded to receive a filling attachment and communicates with thegroove 38 at the corner of the lower mold through a suitable aperture inthe lower gasket, Sprue 76 is preferably provided at the corner of thelower mold which defines the juncture of the two grouted edges of thesheet of FIGURE l. Both mold sections are preferably provided withapertures indicated by dashed lines at 80 adapted to `receive dowels foraligning the mold sections during the molding operation.

FIGURE 8 illustrates one of the -two resilient rubber gaskets utilizedin the mold assembly of the present invention. Since both gaskets areidentical, except that the lower gasket is provided with a filling sprueapertureand exhaust ventapertures, only one is illustrated at 82 inFIGURE 8. FIGURES 9 and 10 are cross-sections taken along lines 9-9 and10-10 of FIGURE 8 respectively. FIGURE 9 illustrates the cross-sectionalconfiguration of gasket 82 through one of the intermediate webs 84which, in conjunction with gasket edges 86, define rectangular openings88. Openings 88 during operation are aligned with the wells 45 formed inthe mold sections as illustrated in FIGURE 2. As seen in FIGURE 9, thelower portion of the gasket 82 is formed of rectangular configurationwith upper tapered surfaces 90 and 92 defining a fiat cenltral band 94.FIGURE 10 illustrates the edge web 86 as having a rectangular bottom, afiat outer surface 96 and a tapering inner upper edge surface 98. Therectangular bottom edges of the gasket 82 are constructed to be receivedin the rectangular channels 32 and 34 of the upper mold section 26. Theupper tapered surfaces of a similarly constructed gasket are likewisereceived in the channels 28 and 3G of the lower mold section 24 ofFIGURES 3-6. While any suitable gasket material may be employed, thegaskets ofthe present invention are preferably formed of silicone rubbersuitably filled for low thermal expansion and pressure set, having ahardness dur-orneter test reading of 68-70. By keeping the crosssectional dimensions of the gasket webs at a minimum, it is possible toreduce the thermal coefficient of expansion of the silicone rubber sothat its effect on the molding process is negligible.

FIGURE ll shows the mold construction during an intermediate stage ofassembly with a separating metallic mold frame 100 about to be placedover the lower mold section 24. Frame 100 is provided with cornerapertures 102 adapted to be received over dowell pins 104 provided inthe lower mold section. One of the gaskets 82 has previously beeninserted in the grooves of the lower mold section and frame lill) isplaced over the gasket. A filling connection 106 is illustrated asthreaded into the sprue hole previously described in the corner of thelower.- mold section. Frame 10i) is provided with adjacent groutingedges 39S and liti which define the grouted edge portions of sheet it*in FIGURE l as well as non-grouted edges il?. and tli.

FIGURE l2 illustrates a further stage of assembly wherein the frame 100is secured over the lower mold section 24 and the tiles 14 are beingplaced over the lower gasket 82. The tiles may be positioned by hand, orif desired, can be placed in position over the gasket by suitableautomatic machinery. The tiles 14 are slightly spaced as indicated at114 to provide an area for the grout material between adjacent tiles.Individual tiles automatically adjust to this spacing because of thecross sectional configuration of the gasket illustrated in FIGURES 8-10.The edges of the tiles tend to Contact the upper edge of slopingsurfaces 9d and SP2 in FIGURE 9 with the spacing 114 approximating thewidth of the at band 94 in FIG- URE 9. Similarly, the tile edges at theouter edge of the tile sheet terminate at the upper edge of beveledsurface 98 formed on the edge webs of the gasket. As a result il ispossible to quicidy place the tiles over the gasket 82 in FIGURE l2without being particular as to placement since the tiles will beautomatically positioned by the beveled surfaces 90, 92 and 98 of theupper gasket when the upper mold section is placed over the tiles. Thetiles 14 in FIG- URE 12 are placed on the flat bottom surfaces o thegasket 82 illustrated in that figure since the beveled edges of thelower gasket are received in the cooperating beveled slots 28 and 30 ofthe lower mold section. Of course by reversing the positions of thegaskets -this automatic spacing can be obtained at the time the tilesare placed on the lower mold section.

FIGURE 13 illustrates the lcomplete mold assembly with the upper andlower sections of the molds securely clamped together by a plurality ofeccentric clamps, one of which is illustrated at 120. The clamp isprovided with an aperture encircling a lower clamping pin 122 andincludes an eccentrically tapering upper arm 124 engaging a similar pin126 in the adjacent mold section. In FIG- URE 13 the mold sections havebeen joined together and inverted so that lower mold 24 now appears atthe top of the mold assembly and upper mold 26 appears at the bottom.The tiles 14 are securely clamped against the upper and lower gasketsbetween the mold sections and a suitable lling line for fluid groutmaterial iudicated at 12S is ready for attachment to the iilling fixturedr spout 1mi. It desired, the mold sections may be reinforced at thecorners by integral yreinforcing blocks 13st).v

The underside or unglazed surface of the tile now faces the ytop of themold assembly in FIGURE 13.

FiGURES i4, l5 and i6 show partial cross sections through the moldassembly of FIGURE 13 and illustrate the manner in which the individualtiles 14 are supported by the resilient gaskets. FIGURE i4 shows a crossscction through an intermediate web of the gaskets with the moldsections inverted so that the lower mold section .72d is above uppermold section 2d in the same manner as is illustrated in FIGURE 13.Adjacent tiles le are spaced by the slanted or beveled surfaces 9d and92 of the lower gasket 82 so as to define the spacing lid betweenadjacent tiles for the fluid grcut material. The tiles 1d are formed ina conventional manner with beveled edges so that the grout spacing isgreater adjacent the glazed surface 130 of the tile.,

FIGURE l5 is a partial cross section through the mold assembly of FIGURE13 along one of the grout edges 16 and 1 8 of the -tile sheet ofFIGURE 1. The adjacent edges 132 of tile 14 and 134 of frame '194i areboth tapered from the back towards the glazed surface 13u of the tileleaving a space 136 to be iilled by the grout 716 or 18. A metallic shim138 is provided between the mold sections 24 and 26 to properly spacethe mold assembly.

FIGURE 16 is a par-tial cross section through a nongrouted edge of themold assembly corresponding to one of the non-grouted edges 2li and 22 othe tile sheet of FIGURE l. Along this edge of the tile ld the framelili? is provided with an inwardly tapering surface Mtl so that ittightly abuts the adjacent edge of the tile 1d. As a result, no fluidgrout is permitted between these adjacent surfaces and the outer edge ofthe tile is grout free.

While the gaskets 82 have been described in conjunction with siliconerubber, other resilient materials maybe used such as plain rubber oriiuorinated silicone, depending upon the type of grout material beingused to grout the tile sheet. ln operation, .the lower gasket 82 isfirst inserted in the tapered grooves of the lower mold section 24. Theframe is Ithen placed on top of the gasket and over the dowel pins inthe lower mold section. Next, the tiles are inserted in place, glazedface up, over the lower gasket with the edges suitably primed if thegrout material is to be a vinyl plastisol. Suitable acrylic or epoxyresins may be used as primers and the plastisol, if desired, may beutilized in conjunction with plasticizers, stabilizers, lillers and thelike. Priming of the tile edges is not needed with some resins such asurethane.

The upper gasket is then inserted in the rectangular channels of theupper mold section and, with the shim in place, is clamped over thelower 'mold section. The assembly is then inverted to .the positionshown in FIG- URE 13 and the supply of liquid grout attached to theiitting 106 in mold section 24. Vent passages are preferably provided inythe mold sections to permit the escape of air from the group passages.Filling or injection of the liquid grout material from a suitablepressurized liquid supply tank is instantaneous and automatic. When thevent holes begin exhausting the liquid grout material, the mold isconsidered filled. The vent holes allow for expansion and overllow ofthe liquid grout material during ythe `fusing cycles.

The tilled and injected mold is then placed in a circul and can beeither air or Water mist to reduce the mold temperature approximately 50F. below fusing temperature. At this point, the mold is opened and thecompletely grouted sheet 1u removed from the mold. v

The mold may be immediately recycled while the sheet just removed fromthe mold is inspected and lightly beltsanded along the two non-groutededges to remove any grout flash that may be present. The belt-sandingstep provides for perfect mating and sealing between grouted ceramictile sheets in comercial installations.

The size of the grout joint \in the embodiment shown, i.e., the spacingbetween adjacent tiles, is 1%;2 of an inch on the glaze face side of thesheet and yg of an inch on the back surface of the sheet. Curing andfusing temperature of the grout material ranges fnom 300-35 F. Curingtime ordinarily runs from 8-10 minutes and the mold is then cooled to 50F. or more below the curing temperatuer by a cold Vapor mist applied tothe mold and glazed tace of the tile for approximately a two-minuteperiod.

FlGURE i7 shows a modiiied mold assembly used in conjunction withelectrical heating. FIGURE 18 shows a partial cross-section through agrouted edge of the mold assembly of FiGURE 17. In FIGURE 17, lower andupper mold sections 24 and 26 are again utilized in conjunction with amodified frame .150. The mold sections 2d and 26 are identical to thosepreviously described with the exception that the injection sprue isomitted from lower mold 2d. Overlying the grillwork of bottom moldsection 2dis a heat insulating silicone rubber gasket liZ having heatingwires 154i embedded therein. Over the grillwork of the upper moldsection 26 is a second silicone rubber gasket ld and lit may also haveheating wires 15S passing therethrough.

Gasket 152 is provided with tlanges 16d and i152'. which overlie acarrissa wood liner 16d. Liner 16d passes beneath lthe gasket andoverlies the upper mold section 2d on both sides of the grooves asclearly seen in FIGURE 18. Lower gasket iSd similarly includes iianges16d and llo@ which overlie a second carrissa wood liner 179. Frame 159is provided with a sprue aperture 172'providing access for iiuid groutto the space `1'74 between the frame and the edge of tile 14. A shim 176is provided for proper spacing. In all other respects, the mold assemblyof FlGURES 17 and 18 is similar to that previously described.

insulating liners 164 and 170 are secured by suitable adhesive to thegrooves or channels in the cast aluminurr mold sections 24 and 26.Gaskets 152 and 156with the heating wires embedded therein, are thensecured by suitable adhesive to .the insulating wood liners. The mol( isassembled as before and may or may not be inverter Ito the positionshown in FIGURE 18 as desired. Thr electric current from a suitablesupply is passed througl wires 154 and 15S to heat the injected groutmateria passed in through sprue aperture 172 to the desired cur ingtemperature. The electric mold of FIGURES 17 an( 18 is not placed in acirculating hot air oven since, by the induction of the electriccurrent, it generates its owr heat because of the heating elementsembedded in thi silicone rubber seals.

Although the invention is described with grou-t materia applied to twoedges, the tile sheets may be pregroute along `any desired number ofedges, adjacent or otherwis By properly spacing the edge tiles from thedividing frarnr or 150 and giving the desired contour -to the inne edgeof the frame, it is possible to vary the thickness am shape of the groutedges in any of a wide variety o ways from zero grout width to fullgrout width or more In some instances, it is desirable to pregrout onlyont edge and in other cases grout around all edges is morl suitable.Furthermore, in certain circumstances, it ha been found necessary tochange the grout configuratioi at different edges such as making someedges full widtl and others only half width. Different grout shapesalon4 different edges xare particularly important in situationsrequiring welding edges for welding Va multiplicity of sheets togetherat `the job site. This welding is accomplished through the applicationof a solvent to the plastisol grout edges and bringing the thus softenededges into .tight adhering contact.

From the above, it is apparent that the present invention provides anovel pregrouting assembly for ceramic tile which accomplishes acommercially acceptable surface grout nish on a completed tile sheet ofany desired number of individual ceramic tiles. Grout material isinjected into the mold system in liquid form and only ccomes fused intoan elastomeric solid at the elevated .ng or curing temperature. The meidsystem is cons..ucted to give good heat conductance, to provide ease ofhandling and to withstand the elevated temperatures :to which it issubjected. The particular groove arrangen ment disclosed isself-cleaning and the aluminum mold elements provide for rapid coolingin conjunction with the generally open framework of Ithe overallconstruction. The mold system provides two adjacent full grout edgesAand two adjacent grout free edges on the ceramic tile sheet. Theappearance of the finished tile is equal to thc best manual jobperformed by a skilled mechanic. Tiles may be assembled on a surface tobe covered much more quickly without requiring the skill and patienceinvolved in present-d-ay hand-tiled construction. The intermediateelastomeric grout material imparts a certain amount of flexibility to-the sheets, thus completely obviating any possibility of breakageduring handling and permitting greater ease of installation.

The invention may be embodied in other specific forms without departingfrom the spirit or essential character istics thereof. The presentembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

1. A mold assembly for forming pregrouted ceramic tile sheets comprisingupper and lower mating mold sections, said sections being formed of aplurality of crisscrossing ribs separated by opened wells, a pluralityof crisscrossing grooves formed in the faces of said mold sectionsmidway of said ribs, a resilient gasket `received in the grooves of eachmold section, said gaskets each forming an aligned lattice network ofcriss-crossing ribs extending above the faces of said mold adapted tosupport the edges of spaced ceramic tiles bridging said wells, means forclamping said mold sections together wherebj" the peripheral edges ofthe tiles are clamped between the aligned ribs of said gaskets to definean enclosed grout space between adjacent tiles. a frame for engaging theperipheral edges of said gaskets, said frame having two adjacent inneredges tapered to tightly abut the edges of the tiles clamped betweensaid mold sections and two other adjacent inner edges tapered to definea space for grout material between said other edges and the edges oftiles clamped between said mold sections, a grout filling spruecommunicating with the juncture of said grout spaces along said twoother edges of Said frame. means for injecting fluid grout material intosaid clamped .mold sections to lill the spaces between adja- Acrossingribs sepa-rated by opened wells, a plurality of criss-crossing groovesformed in the faces of said mold sections midway of said ribs, 'aresilient gasket received in the grooves of each mold section, saidgaskets each forming in aligned lattice network of criss-crossing ribsextending above the faces of said mold adapted 4'to support Vthe edgesof spaced ceramic tiles bridging said wells,

means for clamping said mold sections together whereby :the peripheraiedges of the tiles are clamped between the aligned ribs of the gasketsto define an enclosed grout space between adjacent tiles, the outersurface of one of said gaskets being at and the outer surface of theother of said gaskets being beveiled to define an intermediate rib, saidbevelled surface being formed to engage the bevelled glazed surface edgeof a ceramic tile, lmeans for injecting tiuid grout material into saidclamped mold sections to fill the spaces between adjacent tiles, andmeans for heating said clamped mold sections to cure said grout materialto a exible elastomer.

3. A mold assembly for forming pregrouted ceramic tile sheets comprisingupper yand lower mating mold sections, said sections being formed of aplurality of crisscrossing ribs separated by opened wells, a pluralityof criss-crossing grooves formed in the faces of said mold sectionsmidway of said ribs, a resilient gasket received in the grooves of eachmold section, said gaskets each forming an aligned lattice network ofcriss-crossing ribs extending above the faces of said mold adapted tosupport the edges of spaced ceramic tiles bridging said wells, a heatinsulating liner between said gaskets and said mold sections, means forclamping said -mold sections together whereby 'the peripheral edges 0fthe tiles are clamped between the aligned ribs of said gaskets to defineland enclose grout space between adjacent tiles, .means for injectingliuid grout material into said clamped mold sections to ll the spacesbetween adjacent tiles, and means for heating said clamped mold sectionsto cure said grout material to a exible elastomer comprising an electricheating wire embedded in at least one of said gaskets.

References Cited by the Examiner UNITED STATES PATENTS 2,521,128 9/50Ramsay.

2,572,580 10/51 Almroth et al. 18-59 2,707,802 5/55' Gard.

2,718,829 9/55 Seymour 18--61 2,732,605 1/56 Johnson 18-60 2,777,184l/57 Monk et al 25-1 2,781,554 2/57 Robinson 25--1 2,822,576 2/58 Rowe.

2,825,221 3/58 BrookA 18-61 2,972,783 2/61 Russell et al. 25-1 FOREIGNPATENTS 821,897 10/59 Great Britain.

ALEXANDER H. BRODMERKEL, Primary Examiner.

MICHAEL V. BRINDISI, ROBERT F. WHITE,

MORRIS LIEBMAN, Examiners.

1. A MOLD ASSEMBLY FOR FORMING PREGROUTED CERAMIC TILE SHEETS COMPRISINGUPPER AND LOWER MATING MOLD SECTIONS, SAID SECTIONS BEING FORMED OF APLURALITY OF CRISSCROSSING RIBS SEPARATED BY OPENED WELLS, A PLURALITYOF CRISS-CROSSING GROOVES FORMED IN TE FACES OF SAID MOLD SECTIONSMIDWAY OF SAID RIBS, A RESILIENT GASKET RECEIVED IN THE GROOVES OF EACHMOLD SECTION, SAID GASKETS EACH FORMING AN ALIGNED LATTICE NETWORK OFCRISS-CROSSING RIBS EXTENTING ABOVE THE FACES OF SAID MOLDS ADAPTED TOSUPPORT THE EGES OF SPACED CERAMIC TILES BRIDGING SAID WELLS, MEANS FORCLAMPING SAID MOLD SECTIONS TOGETHER WHEREBY THE PERIPHERAL EDGES OF THETILES ARE CLAMPED BETWEEN THE ALIGNED RIBS OF SAID GASKETS TO DEFINE ANENCLOSED GROUT SPACE BETWEEN ADJACENT TILES, A FRAME FOR ENGAGING THEPERIPHERAL EDGES OF SAID GASKETS, SAID FRAME FOR ENGAGING TWO ADJACENTINNER EDGES TAPERED TO TIGHTLY ABUT THE EDGES OF THE TILES CLAMPEDBETWEEN SAID MOLD SECTIONS AND TWO OTHER ADJACENT INNER EDGES TAPERED TODEFINE A SPACE FOR GROUT MATERIAL BETWEEN SAID OTHER EDGES AND THE EDGESOF TILES CLAMPED BETWEEN SAID MOLD SECTIONS, A GROUT FILLING SPRUECOMMUNICATING WITH THE JUNCTURE OF SAID GROUT SPACES ALONG SAID TWOOTHER EDGES OF SAID FRAME, MEANS FOR INJECTING FLUID GROUT MATERIAL INTOSAID CLAMPED MOLD SECTIONS TO FILL THE SPACES BETWEEN ADJACENT TILES,AND MEANS FOR HEATING SAID CLAMPED MOLD SECTIONS TO CURE SAID GROUTMATERIAL TO A FLEXIBLE ELASTOMER.